The present invention relates to a dialysate preparing apparatus for dissolving powder such as granules with a dissolving solution to prepare a dialysate.
Hitherto, preparation of dialysate has been performed in a tank system. In the tank system, a prescribed quantity of a dissolving solution and a powder are introduced into a solution tank, and then stirred by a stirring pump or a stirring blade to mix and prepare a dialysate. The prepared dialysate is transported to a point of use by a delivery pump. At this time, the level of the solution in the solution tank is lowered, and a negative pressure is generated in the solution tank and thus outside air is introduced into the solution tank. The air introduction occurs in the tank system because the solution tank is generally opened to the air to prevent breakage of the solution tank itself by negative pressure generated therein. Therefore, in many cases, an air filter is provided at a portion opened to the air for preventing bacteria or the like contained in the outside air from entering, which results in many difficulties and a high cost of replacing the air filter on regular basis. As a matter of fact, there are cases where a filter that prevents only dust is used, or even no filter is used considering the difficulties and cost, but this is not preferable. In addition, in the tank system, when an attempt is made to prepare a great quantity of dialysate at a time, a large solution tank is required, thereby disadvantageously increasing the size of the apparatus itself. In addition, since many stirring pumps and delivery pumps are necessary, operating noise may disadvantageously be too loud. When an abnormal concentration is found after preparation, an adjustment of concentration of dialysate cannot be made in the related tank system, whereby the dialysate has to be discarded, which is economically disadvantageous. In addition, in a dialysis apparatus of the related art, a dialysate preparing section and an ultrafiltration control section are separated, whereby the size of the entire apparatus disadvantageously increases.
With the circumstances described above in view, an object of the present invention is to provide a cost effective dialysate preparing apparatus, in which replacement of air filters for preventing bacteria or the like from entering into the solution tank is essentially unnecessary. It is possible according to the present invention to miniaturize the entire system and reduce the operation noise, and further, to finely adjust the concentration of dialysate, and to integrate the dialysate preparing section and the ultrafiltration control section into a single unit.
After dedicated studies, the inventor found that the above- described object can be achieved by utilizing a chamber the inside of which is divided into four compartments: a first compartment, a second compartment, a third compartment and a fourth compartment, by movable partitions so that dialysate can be prepared within a circuit containing the first compartment and the second compartment of the chamber while substantially preventing the outside air from entering therein, and that the capacities of the first, the second, and the fourth compartments can be changed by changing a capacity of the third compartment, and completed the present invention.
In other words, the present invention is a dialysate preparing apparatus comprising a chamber, the inside of which is divided into four compartments: a first compartment, a second compartment, a third compartment, and a fourth compartment, by movable partitions; a dissolving solution supply line for supplying a dissolving solution into the first compartment of the chamber; a dialysate preparing line connecting the first compartment and the second compartment of the chamber; a solution tank connected to the first compartment and a transporting pump connected to the second compartment, both the tank and the pump being provided in the dialysate preparing line; powder supply means provided above the solution tank; a dialysate line for supplying dialysate prepared and filled in the second compartment to a dialyzer and connecting the second compartment to the fourth compartment via the dialyzer; a circulating line connecting the dialysate preparing line between the solution tank and the transporting pump with the dialysate line between the second compartment and the dialyzer; a waste liquid discharge line for discharging used dialysate filled in the fourth compartment; and a concentration meter provided in a circuit comprising the second compartment of the chamber, the dialysate line, the circulating line, and the dialysate preparing line, in which the quantity of the solution supplied to the first compartment, the quantity of the dialysate filled in the second compartment, and the quantity of the used dialysate filled in the fourth compartment can be adjusted by charging and discharging a liquid filled in the third compartment of said chamber.
The solution tank may be provided with a liquid level detecting sensor. The dissolving solution supply line may be provided with a second dissolving solution supply line. In the dialysate preparing apparatus of the present invention, preferably, a second chamber, the inside of which is divided into four compartments by movable partitions, is further connected to the dissolving solution supply line, the dialysate preparing line, the dialysate line, and the waste liquid discharge line of the first chamber, so that the preparation of the dialysate and dialysis can be performed continuously.